| Abstract | The study of species complexes is of particular interest to understand how evolutionary young species maintain genomic integrity. The Daphnia pulex complex has been intensively studied as it includes species that dominate freshwater environments in the Northern hemisphere and as it is the sole North American complex that shows transitions to obligate parthenogenesis. Past studies using mitochondrial markers have revealed the presence of 10 distinct lineages in the complex. This study is the first to examine genetic relationships among seven species of the complex at nuclear markers (nine microsatellite loci and one protein-coding gene). Clones belonging to the seven species of the Daphnia pulex complex were characterized at the mitochondrial NADH dehydrogenase (ND5) gene and at the Lactate dehydrogenase (LDH) locus. K-means, principal coordinate analyses and phylogenetic network analyses on the microsatellite data all separated European D. pulicaria, D. tenebrosa, North American D. pulex, D. pulicaria and their hybrids into distinct clusters. The hybrid cluster was composed of diploid and polyploid hybrids with D. pulex mitochondria and some clones with D. pulicaria mitochondria. By contrast, the phylogeny of the D. pulex complex using Rab4 was not well resolved but still showed clusters consisting mostly of D. pulex alleles and others of D. pulicaria alleles. Incomplete lineage sorting and hybridization may obscure genetic relationships at this locus. This study shows that hybridization and introgression have played an important role in the evolution of this complex. |
| Authors | Vergilino, R (Vergilino, Roland)[ 1 ] ; Markova, S (Markova, Silvia)[ 1,2 ] ; Ventura, M (Ventura, Marc)[ 3,4 ] ; Manca, M (Manca, Marina)[ 5 ] ; Dufresne, F (Dufresne, France)[ 1 ] |
| Text | 204285 2011 10.1111/j.1365 294X.2011.05004.x ISI Web of Science WOS 000288074600012 Reticulate evolution of the Daphnia pulex complex as revealed by nuclear markers Vergilino, R Vergilino, Roland 1 ; Markova, S Markova, Silvia 1,2 ; Ventura, M Ventura, Marc 3,4 ; Manca, M Manca, Marina 5 ; Dufresne, F Dufresne, France 1 1 Univ Quebec, Ctr Etud Nord, Dept Biol, Rimouski, PQ G5L 3A1, Canada 2 Acad Sci Czech Republic, Inst Anim Physiol Genet, Dept Vertebrate Evolutionary Biol Genet, Libechov 27721, Czech Republic 3 Spanish Res Council CSIC, Ctr Adv Studies Blanes CEAB, Biodivers Biogeodynam Grp, Girona 17300, Catalonia, Spain 4 Univ Barcelona, Inst Recerca Aigua, Barcelona 08034, Catalonia, Spain 5 CNR Ist Studio Ecosistemi, I 28922 Verbania, Italy The study of species complexes is of particular interest to understand how evolutionary young species maintain genomic integrity. The Daphnia pulex complex has been intensively studied as it includes species that dominate freshwater environments in the Northern hemisphere and as it is the sole North American complex that shows transitions to obligate parthenogenesis. Past studies using mitochondrial markers have revealed the presence of 10 distinct lineages in the complex. This study is the first to examine genetic relationships among seven species of the complex at nuclear markers nine microsatellite loci and one protein coding gene . Clones belonging to the seven species of the Daphnia pulex complex were characterized at the mitochondrial NADH dehydrogenase ND5 gene and at the Lactate dehydrogenase LDH locus. K means, principal coordinate analyses and phylogenetic network analyses on the microsatellite data all separated European D. pulicaria, D. tenebrosa, North American D. pulex, D. pulicaria and their hybrids into distinct clusters. The hybrid cluster was composed of diploid and polyploid hybrids with D. pulex mitochondria and some clones with D. pulicaria mitochondria. By contrast, the phylogeny of the D. pulex complex using Rab4 was not well resolved but still showed clusters consisting mostly of D. pulex alleles and others of D. pulicaria alleles. Incomplete lineage sorting and hybridization may obscure genetic relationships at this locus. This study shows that hybridization and introgression have played an important role in the evolution of this complex. 20 ID_PUMA cnr.ise/2011 A0 041 Reticulate evolution of the Daphnia pulex complex as revealed by nuclear markers Reticulate_evolution_of_the_Daphnia_pulex_complex_as_revealed_by_nuclear_markers.pdf Articolo in rivista Blackwell Scientific Publications, 0962 1083 Molecular ecology Print Molecular ecology Print Mol. ecol. Print Molecular ecology. Print marinamarcella.manca MANCA MARINA MARCELLA DG.RSTL.094.012 Evoluzione della biodiversita e valutazione della banca degli stadi duraturi di organismi acquatici di laghi remoti |
